Various printing methods which can be used in printing presses are known. One such printing method is inkjet printing or ink-jet printing. In this method, individual droplets of printing ink are ejected from nozzles of print heads and are transferred to a printing material such that a printed image is produced on the printing material. By actuating a plurality of nozzles individually, different printed images can be produced. This method does not involve a solid printing forme, thus it is possible to configure each printed product individually. This allows personalized printed products to be produced and/or allows small batches of printed products to be produced at low cost since no printing formes are used.
The precise alignment of printed images on the front and back sides of a printing material that is printed on both sides is referred to as register (DIN 16500-2). In multicolor printing, the merging and precise correlation of individual printed images of different colors to form a single image is referred to as color-to-color registration (DIN 16500-2). Suitable measures are also necessary in inkjet printing in order to maintain color-to-color registration and/or register.
DE 10 2006 004 341 A1 discloses a pretreatment and/or precoating of nonabsorbent substrates for printing with an inkjet printer using a polymerizable, acrylate-containing ink, in which ink for the inkjet printing is applied to the coating in a time- or space-dependent manner before the application of the ink (inline) to the substrate, or the ink is applied independently of the time at which the coating is applied to the substrate, and the ink applied to the substrate or the coating may optionally be heat treated using a temperature control device.
EP 2 202 081 A1 and JP 2003-063707 A each disclose a printing press, wherein the printing press has a first printing unit and a dryer, wherein the first printing unit has a central cylinder having a dedicated drive motor assigned to the first central cylinder and having at least one inkjet print head.
U.S. Pat. No. 5,566,616 A discloses a printing press which has a rotatable central cylinder, inkjet print heads, a cooling device and a dryer, which operates using temperature and air flow or alternatively using radiation-induced curing.
U.S. Pat. No. 6,053,107 A discloses a printing press which has a driven central cylinder and a dryer having a cooling unit.
DE 10 2011 076 899 A1 discloses a printing press which has at least one printing unit and at least one print head configured as an inkjet print head.
WO 2013/132439 A1 discloses a printing ink for an inkjet printing method. To overcome the problems that arise during indirect inkjet printing when ink is applied to the e.g. silicone-containing transfer tape, the printing ink comprises an organic polymer, i.a. A plurality of ink compositions and ranges for the compositions are disclosed, including water-based inks containing polymers and pigments. In embodiments not specified in greater detail, inks can have pigments having a maximum particle size of 120 μm.
A presentation by Mr. Oliver Baar, which can be retrieved from the Verband Druck und Medien [Association of Print and Media] (VDM) webpage at http://www.verband-druck-bw.de and which was published, according to the VDM webpage, as part of Druckforum [Printing Forum] 2013 held on 1 Feb. 2013 in Filderstadt, describes a web-fed printing press having an inkjet printing unit and as the ink system, a water-based pigment-polymer ink.
Another presentation by Mr. Klaus Eppich, which can be retrieved from the Verband Druck und Medien (VDM) webpage at http://www.verband-druck-bw.de and which was published, according to the VDM webpage, as part of Druckforum 2013 held on 1 Feb. 2013 in Filderstadt, describes a wide range of possible applications for the KBA RotaJET printing press and analyzes these applications in terms of their relevance.
DE 20 2009 003 960 U1 discloses a cooling system for cooling a coated or uncoated fibrous web. In the case of fine paper and cardboard, an effective cooling solution is particularly important in order to cool the web before it is rolled.
In an article entitled “Rauigkeit and Topographie—ein Vergleich unterschiedlicher Messverfahren” [“Roughness and Topography—a comparison of various measurement methods”] by M. Lechthaler and W. Bauer, published in the “Wochenblatt für Papierfabrikation” [“Paper Manufacturing Weekly”], 21-2006, various measurement methods for determining the roughness and topography of paper are described and compared with one another.
DE 600 29 410 T2 discloses inkjet inks that contain, i.a. polymeric binders and colorants, e.g. water-soluble dyes or insoluble pigments.
US 2008/0055385 A1 discloses an aqueous ink which comprises a polymer fraction, and comprises pigments as a coloring agent. A transfer member that has been loaded in advance with a liquid is printed with the ink by means of ink heads, and transfers the print image in an indirect process to the printing material. As printing material, normal paper having moderate roughness, for example, or a smooth, coated paper may be used.
US 2011/0128338 A1 relates to a modular transport system for transporting a printing material through an inkjet printing press. The printing press comprises two modules, each having one or more print heads directed onto the web-type printing material. The transport system is suitable for printing processes in which printing materials are dampened during printing. This applies even to printing materials that tend to stretch in the longitudinal and the transverse direction, as is the case, for example, with cellulose-based printing materials that become dampened by water-based ink.
US 2011/0061826 A1 discloses a multilayer fiber product having, e.g., a weight per unit area of 25 to 100 g/m2 and a method for its production, wherein the method comprises applying a fiber layer which contains a filler and which forms a surface layer of the fiber product to both sides of a center layer comprising at least one fiber layer. In this process, filler material and additive are added to the pulp that is used in the surface layers of the multilayer product. The filler material of the surface layers consists at least partially of cellulose or lignocellulose fibrils, onto which light-scattering material particles have been deposited.